Apparatus for drawing glass.



W. W. PILKINGTON, DEO D.

s. L., R. A & A. 0. PILKINGTON. BXBOUTORS.

APPARATUS FOR DRAWING GLASS.

APPLICATION FILED 111111.25. 1911.

1,131,953, Patented Mar. 16, 1915.

3 SHBETSSHEET 1.

[M /2/410- A W/ W. W. PILKINGTON, DEOD.

S. I... R. A & A. O. PILKINGTON, EXEGUTORS.

APPARATUS FOR DRAWING GLASS.

APPLICATION FILED AUG. 25, 1911.

1,131,953, Patented Mar. 16,1915.

3-SHEET$SHEET 2.

W WL/LQQ? @n W. W. PILKINGTON, DEOD.

s. L.. R. A & A. 0. PILKINGTON. EXBCUTORS.

APPARATUS FOR DRAWING GLASQ.

APPLICATION FILED AUG.25, 1911'.

l, 1 81,953, Patented Mar. 16,1915.

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FJFIQE.

WILLIAM WINDLE PILKINGTON, OF PRESCOT, ENGLAND; SARAH LOUISA PILKINGTON',

RICHARD AUSTIN PILKINGTON, AND

ALFRED CECIL PILKINGTON, EXECUTORS 0F SAID WILLIAM WINDLE PILKINGTON, DECEASED, ASSIGNORS T0 PILKINGTON BROTHERS, LIMITED, 015 ST. HELENS, ENGLAND.

APPARATUS FOR DRAWING GLASS.

Specification of Letters Patent.

Patented Mar. 116, 11911 5.

Application filed August 25, 1911. Serial No. 646,049.

To all whom it may concern:

Be it known that I, WILLIAM WINDLE PILKINGTON, a subject of the King of the United Kingdom of Great Britain and Ireland, residing at The Hazels, Prescot, in the county of Lancaster, England, have invented'new and useful Improvements in or Relating to Apparatus for Drawing Glass, of which the following is a specification.

My invention relates to improvements in apparatus for drawing glass cylinders.

In drawing glass cylinders, the cylinder is drawn at a rate which varies from start to finish, the rate of draw at the start and at the finish being such as to produce special I formations of the ends of the cylinder, and

the rate of draw of the main body of the cylinder being gradually increased to compensate for the gradual cooling of the glass in the pot. At the same time and for the same reasons the rate of supply of air to the cylinder is varied from start to finish.

These variations in the rate of draw and in the rate of supply of air are usually produced by automatic devices acting in conjunction With a Winding apparatus running at constant speed and with a supply of air under constantpressure, the variations at the start and the finish being sometimes produced by hand regulation instead of automatically. The ordinary automatic device for varying the rate of draw consists of a conical pulley or drum on the winding apparatus. The ordinary automatic device for varying the rate of supply of air consists of a valve in the air siipply pipe or in a vent from the pipe, which is acted on directly or indirectly by gear and link-work from the winding apparatus. Now in such apparatus, while it is possible to vary the rate of draw throughout the operation by altering the constant speed of the winding apparatus, and to vary the rate of air supply throughout the operation by altering the constant air pressure or adjusting the valve, or the link-work actuating the valve, it is not possible, without altering the mechanical device determining the rate of variation, to alter the relative rates of variation of either factor from one point to another of the draw, or, as I shall term it hereinafter, to after the law of-variation of either factor.

.eifect an alteration inthe law of variation of the rate of air supply, in consequence of alterations in the temperature and nature of the glass,- and in the temperature of the atmosphere, and for other reasons. Moreover it is found.that if the rate of draw be changed in any way, without changing its law of variation, a change has to he made in consequence, not merely in the rate of air supplied but in its law of variation.

The object of the present invention is to provide devices determining the law of variation of the rate of air supplied, which can be easily and quickly adjusted so as to give any desired law of variation in the rate.

According to my invention the law of variation is determined wholly or in part by the surface ofa cam, the cam being of such construction that the form of its surface can be easily and quickly changed.

I do not confine myself to the use of any particular construction of variable cam, and it is to be understood that I make no claim to a variable cam of any construction apart from its application to apparatus for drawing glass.

In applying the device I may employ one of two methods. According to the first, I actuate the cam either at constant speed by a suitable motor, as for instance by the motor driving the winding apparatus, or at a variable speed by the drawing carriage or its connections. regulating the supply of air by means of say, a lever having a wiper or roller bearing on the cam surface. According to the second method the supply of air is regulated by any of the methods ordinarily employed so as to give an approximately correct aw of variation, and I cause the wiper or roller bearing on the cam surface to actuate an auxiliary valve such as a valve in a by-pass around the main valve, or to superimpose an auxiliary motion on the motion of the main valve, thus super-imposing variations on what may be regarded as the normal or average law of variation.

The functions of the cam and of the wiper I then actuate the valve 4 another cam which stance, the motor may or roller may be reversed so that the cam is the driven part and the Wiper or roller the driving part.

In the accompanying drawings which are to be taken as part of this specification and read therewith, Figure 1 is an elevation partly broken away, of one form of variable cam with the air valve actuated by it; Fig. 2 is a vertical section thereof, the air valve being omitted except for the roller of the \lever thereof; Fig. 3 is an elevation of another form of variable cam, part of the lever only of the air valve is a diametral section on-the line 4-4 of Fig. 3; Fig. 5 is an elevation of another form of variable cam; Fig. 6 is a diametral section on the line an elevation and Fig. 8 a vertical section of formof variable cam; Fig. 9 is an elevation of part of another form of variable cam; Fig. 10 is a vertical section on the line 10-10 of F ig..9, and Fig. 11 is a diagrammatic view of another form of the can be applied to the purposes of this invention. 1

Referring tothe device shown in Figs. 1

and 2, 1 is a flexible strip of steel held in I cha'nnel clamps or clips 2 having their ends turned in, as shown in-Fig. 2, the strip being free to slide through the clamps. These clamps are pivoted to screwthreaded rods 3 which pass loosely through holes in a bar 4 and are adjustably secured to the latter by wing nuts 5 and'6.

between two angle iron guides 7 and 8 forming the supporting framework, and it is' supported on them by cross pieces 9 secured to the said bar. The bar 4 with the rods 3. and flexible strip lthus attached to it, is moved endwise' by the drawing apparatus. or an independent motor to which it is attached in any convenient manner.

drive a worm wheel 7 42 to which, as shown in Fig. 1, is attached 4'. of thea'irvalve 13 is s the surface of the strip by a tension As the bar'4 is moved in correspondence. wi th the progress of the draw, so the air, i valve 13 is opened or closed in correspondv 5 once with the form given the supply 'pfair at any a nut 43, carried on fixed bearings 44 and "engaging with a screw 10 fixed to the bar,

A roller 11 on the kept in contact. with spring 14.

1. i The form-of the strip 1 and consequently may be'v'aried by loosening one and tightening the'other of the two wing nuts 5 andy do '6' on any of the rods 3. Such variation may I I another but be effected not merely between one draw and during the progress of a draw.

Figs. 3 and 4'show a device similar to that just described, but mounted on a disk which 1s rotated by a connection to the drawing apparatus or otherwise. he

being shown; Fig. 4

6--6 of Fig. 5; Fig. 7 is The bar 4 is guided containing a number of thin plates 26.

These plates can For. in-

endxof the lever 12 .7, 8 by means '0 brackets ,frame, and it is arranged to to the flexible strip v [V108, consisting .of point of the draw somewhat 1 nuts 20 on the studs 17. The form of the strip 15 can be varied by moving one or more of the clamps 16 along the respective slots 18, the clamps being free "to turn and adapt themselves to varying tangents of the strip.

Figs. 5 and 6 show a third form .of the device which, like that last described, is mounted on a rotating disk 19. A bar 21, fixed to the disk 19, is given a form approximating to the general form which it is desired to give to the cam. A number of set screws or bolts 22-pass through the bar 21 and serve to keep a flexible strip 23 at varying distances from the ban The strip 23 is held in contact with the outer ends of the set screws 24 which is held taut by .being attached. to the disk 19 at its respectively opposite ends. The spiral spring 24 serves also as the sur-. face on which the roller 11 bears, and it is prevented from shifting by means of a as by bolts and the sake of clear- Fig. 5, aswith ring 35, Fig. 6, secured, nuts'36, to the bar 21; for ness the device is shown in the ring 35 removed.

Figs. 7 and 8 show a fourth form of the device, consisting of a rectangular frame 25 give any ,deslred general contour to the surface formed by their ends, by tapping them smartly. When their ends have been tapped so that collectively they give the desired former general contour of surface, they are clamped firmly inpositionby tightening up thehandserew 27. The whole frame 25 is supported and 'uidedon v 28 fast'to the'said wise by a screw 10, as in the form herein first. described. I a Figs. 9 and 10.sho w a fi'fthform of the dea ,bar 29 longitudinally reciprocated as in the deviceillustrated in Figs.- 1 and .2 ,.and' carrying a number of plates30, 31, pivoted to the bar'29 by means of bolts .32, provided with nuts 33 by which of devicethe lates can be tightened against the bar. Eac .plate 30 lies close against the bar 29 the other plates (31) being held away from the bar by washers 34, Fig. 10, so that they can overlap the plates 30. The upper overlapping edges of the plates 30, 31 are so 22 by a spiral spring angle iron guides be moved endshaped as to form a cam surface of approximately the desired contour. the nuts 33 on the respective bolts 32, the plates 30, 31 can be turned about the said bolts so as to vary the shape of the cam surface formed by their upper edges, Without materially disturbing the continuity of such surface, the said plates bein afterward secured in-their adjusted positions by again tightening the nuts 33.

The invention includes any modification characterized by the base-line of the cam being circular instead of straight or straight instead of circular, the Variations of a cam surface having a circular base-line, being in respect of direction, allel with, the axis of rotation. By baseline is meant the line from which a draftsman'sets off the variations in the cam surface. The top line 37 of the bar 4 in Fig. 1, or any line parallel with it, as Well as the circle 38 in Fig. 5 or any circle concentric with it, are both such base lines. Fig. 11 illustrates diagrammatically one modification characterized by the variations of the cam surface 39 being parallel in respect of direction with the axis 40, 41 being the baseline. I

The flexible-member forming the cam surface may be composed of lead or rubber or of a spiral spring or of a combination of these or other materials or devices.

The flexible strips 1 and 15 constituting,

By loosening either radial to, or paras they do, the actual cam-surfaces, as hereinbefore described, are for convenience, hereinafter referred to in the claims as flexible strip cams. In the following claims I use the cinematical term cam pair to designate the combination of two members, one a cam surface and the other a means cooperating therewith, such as a wiper or roller.

Having described my invention I declare that What I claim and desire to secure by Letters Patent is 1. In apparatus for drawing glass, a variable cam pair of which one member is operatively connected with the drawing gear and the other member is operatively connected with a valve in the air supply system.

2. In apparatus for drawing glass, the combination with a flexible strip cam of a bar supporting the said strip cam, adjustable means connecting the strip cam to the bar or adjusting the distance between relatively opposite points in the said strip cam and bar, means operative to move the bar longitudinally and means cooperating with the flexible strip cam to operate a vali e in the air supply system.

In witness whereof I have hereunto set my hand in the presence of two Witnesses.

WILLIAM WINDLE PILKINGTON.

Witnesses:

JOHN LEONARD JACKSON, JOHN HAROLD DICKINSON. 

